Quick-detachable dustcap



March 4, 1930. E. F. TOBOLD 1,749,170

QUICK DETACHABLE DUSTCAP Fii ed April 18, 192'! I Patented Mar. 4, 1930 1 EwALn'r. TOBOLI), or CLEVELAND,

01110, ASSIGNOR TOTI-IE DILL MANUFACTURING -COMPANY, 01F CLEVELAND, OHIO, .A CORPORATION OF OHIO QUICK-DETACHABLE DUSTCAP Application filed April is,

. Thepresent invention relates to dust capsof the type and kindwhich are adapted to be associated with the valve stem of a pneumatic tire or other pneumatic device.

One of the objects of the invention is to provide a construction in which the dust cap c maybe quickly "attached and detached from the valvestem without the necessity of turningthe dust cap along the'entire threaded stem, .as is customary with the usual type of dustjcap, in which the dust cap is provided with a threaded portion at the open end of the cap.

A further object of theinvention is to pro-- vld-ea means associated with the shell of a ,dust cap by whichlmeans the shell of thedust cap is fitted to the valve stem by an expanding action of the attaching means when the dust cap isj mounted upon the end of the valve stem.f v or c further objectof the invention is to pro- ,vide adevice,ofthecharacter described, in "which the attaching means is formed from sheet metalby a stamping operation, where- .bythere is produced an attaching means at a "low cost ofmanufacture;

j Y Reference should be had to the 1, .I j

fjF ig. 1 is an elevation showing a dustlcap a-2 f Fig.1; i Fig.

Otherlobjects of the invention will appear ia'sthe descriptionproceeds. I accompanyingdrawing in which:

,iem'bodying the present invention i Fig. 2 is a sectional plan view'on' the line isasectional plan view'o'n the line j Fig. 4 is a sectional elevation showing in de'tail certain featu res of. construction.

"fjRefer-ring'to' the drawing, 1 indicates the 'shell' of a dust cap, which dust. cap ispref- 'er'ably formed so as to have a plurality offiat "side faces as indicated at 2.

the upper endof the dust capthereis 'fprovided'an extension?) in whichis formed --4-5 t an v rse slotl l which serves as a screw driver member by which valve insides, which fare customarily mounted within the valve zstem,may be insertedand removed. Y

. i Th'e valve stem, in which the device is adapted tocooperate,isfindicated. atf5, and is 1927. Serial No. 184,479.

ofthe usual construction having the outer end of reduced diameter, and threaded, as indicated at 6. i V

Within the shell 1 is what I would term an attaching member which is so called because it serves to form an attachment between the shell of the dust cap and the ,valve stem when the attaching means is secured upon the end 6 of a valve stem. This attaching member is generally represented at 7.

The attaching member is formed with a central body portion 8, which is interiorly threaded, and also forming a part of the member 7 are a plurality of resilient fingers 9. These resilient fingers at their outer ends are formed with an inwardly extending shoulder 10, and with outwardly extending portions 11.

The construction which has so far been described may readily be formed from sheet metal by a stamping process, in which a portion ofthe sheet metal is formed with'an upstanding flange forming the body portion gers 9 are in frictional engagement with the wall of the shell, the friction being suflicient to retain the attaching member in any adjusted positionwithin the shell and, yet, the at taching member may be moved within the shell by asliding'actlon.

An expandingmember 12, which is preferably cylindrical in shape, is mounted within the fingers 9 and is of such diameter that it is normally retained within the resilient fingers 9 by the inturned portions 10 of the resilient fingers. In other words, the diameter of the expanding member 12 is slightly greater than the distance between the inturned portions 10 of oppositely disposed fingers 9.

This expanding member 12 is formed of sheet metaland has a'depending flange 12 so that the general structure of the member 12 may be described as cup-shaped. This member12 is formed with a central dome-shaped portion 12 for a purpose which will be presently described.

Within the member 12 there is a sealing member, the function of which is to seal the end of the valve stem so as to prevent the escape of air which might occur incident to air leakage of'the valve insides. The. seal- 2 ing member also has an additional function,

namely, "that of causing the member 12' to be pushed upwardly or outwardly when the sealing member comes into'engagementwith the end of a valve stem. The sealing member, whlch 1s generally lllCllCfLtBd' at 13,115; cupshaped and has a flange 14: and dome-shaped portion 15.

' WVithin the member 13 there is a molded rubber body which is indicated at 16. This molded body substantially fills the cupshaped member 13 but the central portion thereof is recessed, as indicated at 17, so as to provide a clearance spacefor the upper end of the small valve stem of the valveinsides which frequently extends a slight dis tance beyond the end of the valve stem 5. Obviously, it is desirable to provide clearance for the small valve stem so as not to depress thesame when the dust cap is mounted on the end ofthe valve stem. 7

The dome-shaped port-ion 15 of the member 13 is of a slightly less radiusthan the-domeshaped portion 12 of the expanding member, so that when the dome-shaped portion 15 engages, with the dome-shaped portion 12 there is a limited surface engagement which will permit relative movement between the expandingmember 12 and the member'13. In fact, the intention is that the memberl3 shall be of such dimensions as to readily move with respect to the member '12 and the two'members 12 and 18 may have a swivelacti'on with respect to each other. 7

When the dust cap with the attaching member, which has been described, is inserted over the end of avalve stem, the threaded portion of the part Swill engage withthe threads onthe end f the'valve stem and a rotary movement will causepart8 to travel along the threads of the valvestem. The end of the valve stem;6 will engage withthe rubportion of the sealingmember 13 and as rotation of the part 8' is continuedthe imem-q her 13 will push outwardly upon thefexpan'ding member 12. "Thisoutwardmovement of the part f12 Willcauseth'e same toengage with i theinturnedportion 10' of the fingers 9 and press these. fingers outwardly, particularly the portions 11 ofsaid fingers, into engagement with the innerwall of the shell 1.2The

frictional engagement is very pronounced, in fact'so pronounced that the shell is'effectively held from movement and so is, in effect, attached tothe valve stem 5..

ltwill be apparent from theforegoing 'de scription that it requires only a few turns of. the portion 8 upon the end of the valve stem 6 to accomplish the desired result, so that the dust cap maybe quickly attached and quickly detached from the valve stem. 7

It will be apparent that when the rubber portion 9 of thesealing member has engaged 7 withthe end of ;the valve stem 6, it is quite essential toobviate rotation between the rubber. portion and-[the end" of thevalve stem, .because such rotation would tend to wear andldestroy the rubber. 'gHoweveminasmuch 75,

as h du t c p; nd then-attaching means must be rotated in order to secure attach ment, .the swivel action between the sealing member 13 and the'expanding member 12' is provided so that the two parts mentioned 0, 1 1 may turnor swivel with respect to each sheetmetal by the use of dies. Furthenithe 190 expanding member 12, may be readilyjformed p from sheet metal and the capportion 1319f, the sealing member may also be, formed of sheet metal.

' Thiswill obviate the makinglofthese parts 5 from solid bar metal byithe screw iachine process and thereby production.- 7

The matter important because such structures, ashorein described, ar.e competitive with respectto the ordinary form of dustcapWhichaas'is wellknown, comprises a shelliclosedat one .end and open at the other ,end'with theIinner 3.106

portion of the shell at theopenend provided with screw threads. Such {devices readily perform the function ofprotectingthe .end of valve stems but have the disadvantage of requiring considerable time in the mounting and unmounting of suchdustcaps fromi-the valve stem, due .to the fact that theymust be screwed along the entire body. portion of the valve stem.

, "The quick detachable dust cap herein sdis- 11 15 closedhas a decided advantage over'the old form in the matter of the .quicknessofattaching 1 and detaching, f and-also linf'the mat. ter of more positiveholding,.butlnevertheless itisimperative that the vcost,ofln arul facturing quick detachable dust caps shall not be too great cover-the cost ,ofnianu'facturing theordinary plain dust cap.

. Having thus described any '1inve'ntion,,I Claim: I, a v v I 1-. .A dust cap the other end, an attaching jmemberi Within said shell having a body portion which is adapt d t bem t sspee eed -eta A? greatly lower-"the c t f p p of providing .dustf'cap construction at a low cost of'manufacture; is 1 00 I construction comprising :ai shell which-is closed at one .end .and open at v I valve stem, a plurality of upturned resilient fingerscarried by the body portion,

shaped memberencircled by the said resila cupient fingers, a sealing'member mounted within said cup-shaped member and free to turn with'respect thereto, said fingers havin portions adapted to beengaged by the sai cup- 'd end ofa valve stem.-

' shellwhich is closed at one 7 the other, attaching member within said I shell'and adapted to'beattached to the end i I resilient fingers carried by the body portion,

I shaped member to move them outward when mounted upon t the attaching member is 2. A dust cap construction comprising a end and open at ofa valve stem, a plurality of upturned a cup-shaped expanding member encircled lbythe said fingers, a sealingmember com- I prising a cup-shapedporti'on adapted to fit Within. theexpanding member and to have 7 relative "movement with respect thereto, a

r packing material 'within the last cup-shaped i member adapted to engage the end of a valve v stem, the said fingers having means engaged 25 by the said expanding member to'move the fingers outwardly when the attaching. mem- I ber is secured upon the end of a valve stem.

' shell having a body portion with a threaded 3. A dust cap construction comprising a shell which is closed at one end and open at the otherend, an attaching member within said opening adapted to engagewith the end of a valve stem, a plurality of upturned resilient fingers carried by the body portion, an expanding member encircled by the said fingers, a sealing means associated with the said expanding member and capable of relative turningmovement with respect to the 1 exsignature.

I ,panding member, the saidresilient fingers having means adapted to be engagedby the expanding member to move themoutwardly when the attaching member is mounted upon the end of a valve'stem.

In testimony whereof, I hereunto afiix my EWALD F. TOBOLD. 

